Omicron variant multiplies by 2.4 the risk of reinfection by COVID-19, according to study

Omicron coronavirus variant more likely to cause reinfection than previous variants such as Beta and Delta, this based on a scientific study preliminary published today, according to the Infobae portal.

Statistical analysis of some 2.8 million coronavirus positive samples in South Africa led the researchers to conclude that the new mutation has a “substantial ability to evade immunity from a previous infection.” A new study found that you are 2.4 times more likely to be reinfected with Omicron than previous variants; however, it is not clear whether it causes more serious illness or death.

South African scientists found that reinfection may partially explain how the new variant has spread. They specified that the high risk of being reinfected is “temporarily consistent” with the appearance of the Omicron variant in South Africa.

“The previous infection used to protect against Delta, but now with Ómicron that doesn’t seem to be the case. We monitored these reinfections for the Beta and for Delta, and we did not see an increase in reinfections above what we would expect when the strength of the infection changes, when the wave stops. However, we are seeing an increase for Omicron, ”explained Dr. Anne Von Gottberg, a microbiologist with the National Institute of Communicable Diseases in South Africa at a press conference organized by the World Health Organization (WHO) this morning.

Re-infection rate and vaccine protection

Von Gottberg did not specify the reinfection rate for Ómicron compared to the reinfection rate for Delta; however, he mentioned that having had the disease in previous months should still protect against serious illness, hospitalization, and death from a new infection.

Although questions about the level of protection that vaccines provide against the new variant remain unanswered, Juliet Pulliam, a South African-based epidemiologist and one of the study’s authors, said the vaccines are likely to continue to offer the most effective protection. against serious illness and death.

“Knowing that Ómicron can lead to more reinfections is important”, wrote Pulliam en Twitter.

“Our most urgent priority now is to quantify the extent of Omicron’s immune escape for natural and vaccine-derived immunity, as well as its transmissibility relative to other variants and its impact on disease severity,” said Dr. Harry Moultrie. , an infectious disease expert who co-wrote the study.

Cases and mutations

South Africa’s coronavirus cases nearly tripled in three days as fears about Omicron mount. The Omicron variant has 50 mutations, more than 30 of which are in the spike protein, used by the coronavirus to enter and infect cells, compared to the Delta variant, which remains the predominant variant, has seven mutations in the spike protein.

Other variants are known to cause reinfection: earlier this year they were identified in Israel primarily with the beta variant. But the latest study suggests that the relative risk of re-infection was stable in other variants, underscoring the importance of the Omicron findings.

“Contrary to our expectations and experience with the previous variants, we are now experiencing an increased risk of reinfection that exceeds our previous experience,” said Pulliam.

For its part, South Africa’s National Institute for Communicable Diseases said Wednesday that Omicron outperformed other variants of the virus in November, accounting for 74% of genomes sequenced last month, where Delta had previously been dominant.

Regarding the general number of cases, this has also increased rapidly during the last three days. “Omicron is probably the fastest spreading variant South Africa has ever seen,” said Tulio de Oliveira, professor of public health at Stellenbosch University in South Africa.

Only 6% of Africa’s population has been fully vaccinated. In South Africa, just under 30% of people have been fully immunized, according to Our World in Data.

However, the country’s public health officials warned that misinformation on social networking sites is hampering implementation, especially among young adults.

– Given –

400 cases of Omicron have been detected in 32 countries, including the US, UK and Canada.

In South Africa, cases have risen dramatically from 500 per day two weeks ago to 11,535 per day. Also, the percentage of tests that tested positive increased from 16.5% on Wednesday to 22.5%.

Hospitalizations have also risen with 1,172 South Africans admitted to public and private hospitals yesterday compared to 1,250 people hospitalized in the first four days of this week alone.